/*****************************************************************************
*
*  PROJECT:     Multi Theft Auto v1.0
*  LICENSE:     See LICENSE in the top level directory
*  FILE:        SharedUtil.Hash.hpp
*  PURPOSE:
*
*  Multi Theft Auto is available from http://www.multitheftauto.com/
*
*****************************************************************************/

namespace SharedUtil
{

    #define S11 7
    #define S12 12
    #define S13 17
    #define S14 22
    #define S21 5
    #define S22 9
    #define S23 14
    #define S24 20
    #define S31 4
    #define S32 11
    #define S33 16
    #define S34 23
    #define S41 6
    #define S42 10
    #define S43 15
    #define S44 21
    
    CMD5Hasher::CMD5Hasher()
    {
    }
    
    
    CMD5Hasher::~CMD5Hasher()
    {
    }
    
    bool CMD5Hasher::Calculate( const char* szFilename, MD5& md5Result )
    {
        //CRYPT_START
        // Try to load the file
        FILE* pFile = fopen ( szFilename, "rb" );
        if ( pFile )
        {
            // Init
            Init ();
    
            // Hash it
            unsigned char Buffer [1024];
            while ( unsigned int uiRead = static_cast < unsigned int > ( fread ( Buffer, 1, 1024, pFile ) ) )
            {
                Update ( Buffer, uiRead );
            }
    
            // Finalize
            Finalize ();
    
            // Close it
            fclose ( pFile );
    
            // Success
            memcpy ( md5Result.data, m_digest, 16 );
            return true;
        }
    
        // Failed
        return false;
        //CRYPT_END
    }
    
    
    bool CMD5Hasher::Calculate( const void* pBuffer, size_t sizeLength, MD5& md5Result )
    {
        //CRYPT_START
        // Hash it
        Init ();
        Update ( (unsigned char*) pBuffer, (unsigned int)sizeLength );
        Finalize ();
    
        // Copy out the MD5 and return success
        memcpy ( md5Result.data, m_digest, 16 );
        return true;
        //CRYPT_END
    }
    
    
    void CMD5Hasher::ConvertToHex( const MD5& Input, char* pBuffer )
    {
        for ( int i = 0; i < 16; i++ )
        {
            sprintf ( pBuffer+i*2, "%02X", Input.data [i] );
        }
    
        pBuffer [32] = '\0';
    }
    
    
    SString CMD5Hasher::CalculateHexString( const char* szFilename )
    {
        MD5 md5;
        CMD5Hasher Hasher;
        if ( Hasher.Calculate ( szFilename, md5 ) )
        {
            char szHashResult[33];
            Hasher.ConvertToHex ( md5, szHashResult );
            return szHashResult;
        }
        return "";
    }
    
    SString CMD5Hasher::CalculateHexString( const void* pBuffer, size_t sizeLength )
    {
        MD5 md5;
        CMD5Hasher Hasher;
        if ( Hasher.Calculate ( pBuffer, sizeLength, md5 ) )
        {
            char szHashResult[33];
            Hasher.ConvertToHex ( md5, szHashResult );
            return szHashResult;
        }
        return "";
    }
    
    
    void CMD5Hasher::Init()
    {
        // Nothing counted, so count=0
        m_count[0] = 0;
        m_count[1] = 0;

        // Load magic initialization constants.
        m_state[0] = 0x67452301;
        m_state[1] = 0xefcdab89;
        m_state[2] = 0x98badcfe;
        m_state[3] = 0x10325476;
    }
    
    
    void CMD5Hasher::Update( const unsigned char *input, unsigned int input_length )
    {
        //CRYPT_START
        unsigned long input_index, buffer_index;
        unsigned long buffer_space;                // how much space is left in buffer
    
        // Compute number of bytes mod 64
        buffer_index = (unsigned int)((m_count[0] >> 3) & 0x3F);
    
        // Update number of bits
        if (  (m_count[0] += ((unsigned long) input_length << 3))<((unsigned long) input_length << 3) )
        {
            m_count[1]++;
        }
    
        m_count[1] += ((unsigned long)input_length >> 29);
    
    
        buffer_space = 64 - buffer_index;  // how much space is left in buffer
    
        // Transform as many times as possible.
        if (input_length >= buffer_space) // ie. we have enough to fill the buffer
        {
            // fill the rest of the buffer and transform
            memcpy ( m_buffer + buffer_index, input, buffer_space );
            Transform ( m_buffer );
    
            // now, transform each 64-byte piece of the input, bypassing the buffer
            for (input_index = buffer_space; input_index + 63 < input_length; input_index += 64)
            {
                Transform (input+input_index);
            }
    
            buffer_index = 0;  // so we can buffer remaining
        }
        else
        {
            input_index = 0;     // so we can buffer the whole input
        }
    
        // and here we do the buffering:
        memcpy ( m_buffer + buffer_index, input + input_index, input_length - input_index );
        //CRYPT_END
    }
    
    void CMD5Hasher::Finalize()
    {
        unsigned char bits[8];
        unsigned int index, padLen;
        static unsigned char PADDING[64]={
        0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
        };

        // Save number of bits
        Encode (bits, m_count, 8);

        // Pad out to 56 mod 64.
        index = (unsigned long) ((m_count[0] >> 3) & 0x3f);
        padLen = (index < 56) ? (56 - index) : (120 - index);
        Update (PADDING, padLen);

        // Append length (before padding)
        Update (bits, 8);

        // Store state in digest
        Encode ( m_digest, m_state, 16 );

        // Zeroize sensitive information
        memset ( m_buffer, 0, sizeof (*m_buffer) );
    }
    
    void CMD5Hasher::Transform ( const unsigned char block [64] )
    {
        unsigned long a = m_state[0], b = m_state[1], c = m_state[2], d = m_state[3], x[16];
    
        Decode (x, block, 64);
    
        // Round 1
        FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
        FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
        FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
        FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
        FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
        FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
        FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
        FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
        FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
        FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
        FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
        FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
        FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
        FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
        FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
        FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
    
        // Round 2
        GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
        GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
        GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
        GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
        GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
        GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
        GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
        GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
        GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
        GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
        GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
        GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
        GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
        GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
        GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
        GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
    
        // Round 3
        HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
        HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
        HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
        HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
        HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
        HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
        HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
        HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
        HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
        HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
        HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
        HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
        HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
        HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
        HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
        HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
    
        // Round 4
        II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
        II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
        II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
        II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
        II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
        II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
        II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
        II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
        II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
        II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
        II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
        II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
        II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
        II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
        II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
        II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
    
        m_state[0] += a;
        m_state[1] += b;
        m_state[2] += c;
        m_state[3] += d;
    
        // Zeroize sensitive information.
        memset ( (unsigned char*) x, 0, sizeof (x) );
    }
    
    void CMD5Hasher::Encode( unsigned char *output, unsigned long *input, unsigned long len )
    {
        unsigned int i, j;

        for (i = 0, j = 0; j < len; i++, j += 4) {
        output[j]   = (unsigned char)  (input[i] & 0xff);
        output[j+1] = (unsigned char) ((input[i] >> 8) & 0xff);
        output[j+2] = (unsigned char) ((input[i] >> 16) & 0xff);
        output[j+3] = (unsigned char) ((input[i] >> 24) & 0xff);
        }
    }
    
    void CMD5Hasher::Decode( unsigned long *output, const unsigned char *input, unsigned long len )
    {
        unsigned int i, j;

        for (i = 0, j = 0; j < len; i++, j += 4)
            output[i] = ((unsigned long)input[j]) | (((unsigned long)input[j+1]) << 8) |
                (((unsigned long)input[j+2]) << 16) | (((unsigned long)input[j+3]) << 24);
    }
    
    inline unsigned long CMD5Hasher::RotateLeft (unsigned long x, unsigned long n )
    {
        return (x << n) | (x >> (32-n));
    }
    
    inline unsigned long CMD5Hasher::F ( unsigned long x, unsigned long y, unsigned long z )
    {
        return (x & y) | (~x & z);
    }
    
    inline unsigned long CMD5Hasher::G ( unsigned long x, unsigned long y, unsigned long z )
    {
        return (x & z) | (y & ~z);
    }
    
    inline unsigned long CMD5Hasher::H ( unsigned long x, unsigned long y, unsigned long z )
    {
        return x ^ y ^ z;
    }
    
    inline unsigned long CMD5Hasher::I ( unsigned long x, unsigned long y, unsigned long z )
    {
        return y ^ (x | ~z);
    }
    
    inline void CMD5Hasher::FF ( unsigned long& a, unsigned long b, unsigned long c, unsigned long d, unsigned long x, unsigned long  s, unsigned long ac )
    {
        a += F(b, c, d) + x + ac;
        a = RotateLeft (a, s) +b;
    }
    
    inline void CMD5Hasher::GG ( unsigned long& a, unsigned long b, unsigned long c, unsigned long d, unsigned long x, unsigned long s, unsigned long ac )
    {
        a += G(b, c, d) + x + ac;
        a = RotateLeft (a, s) +b;
    }
    
    inline void CMD5Hasher::HH ( unsigned long& a, unsigned long b, unsigned long c, unsigned long d, unsigned long x, unsigned long s, unsigned long ac )
    {
        a += H(b, c, d) + x + ac;
        a = RotateLeft (a, s) +b;
    }
    
    inline void CMD5Hasher::II ( unsigned long& a, unsigned long b, unsigned long c, unsigned long d, unsigned long x, unsigned long s, unsigned long ac )
    {
        a += I(b, c, d) + x + ac;
        a = RotateLeft (a, s) +b;
    }
}